Coupling



Dec. 18,1923. @www E. E. JOHNSON COUPLING Fiied Feb. 13. 1920 17V vE/v TUR: EDWARD E. JbHNsoN.

A 7' TUR/v5 Ys.

DW..RB E. JOHNSSN, OF ST. EAUL, IVNNESOTA.

LApplisation -led February 13, 1920.

To all whom t fin/my concern.'

Be it known that l, Env/nin E. JoriNsoN, citizen ofthe United l@rieures residing at Paul, in the county oie Ramsey `,and State or i -i-iriesota, have invented .cert in Anew and-useful linproveiiients in Couplings I a xef-:pedii'iiously and economically.

V"llihe -f-ull obgects and advantages of lmy invention will appear in connection with the ldetailed description thereof and the novel feat 1es embodied in iny inventive idea will be paieicularly pointed out .in the claims.

ln the accompanying drawings, 4which illustrate my 1i-nvention,.

Fig. l is a View in side elevation. Fig. 2 isan end View. Fig. 3 is a view on an enlarged scalefinlongitudinal section on the Y line 3 3 of Fig. 2. Fig. 1l is a view in crosssection on the line d-#l oit Fig. 3. Fig. 5 is a View in cross-section on the line 5-5 oi' Fig. 3. F ig. 6 is a View in side elevation viewed from a different position from that shown in Fig. l. Fig. 7 is a side elevational view of a slight modification.

Referring to the construction shown in the drawings, my coupling comprises a hollovv member having a middle portion the exterior of which is polygonal in shape, the sides or faces being designated by the charaoter 10 and the member having reduced end portions, the exterior of both end portions being polygonal in shape and the sides or faces being designated by the character l2.

The exterior conliguration of the middle and end portions is polygonal in shape as stated, and preferably iexagonal. The sides or faces l2 are separated by ribs 14C which start flush With the sides 'l0 and converge slightly as they extend toward the ends of the coupling. The sides l2 are depressed below the level of the sides 10 and they may also converge slightly as they entend toward the ends of the coupling. The outer portions of the sides l2 have elevations 16 the sura-ces of which are substantially parallel with the surfaces of the corresponding sides d durable coupling -niay lbe manufactured' 4Serial No. 358,41?.

l0 respectively. The interior surface of the ycoupling is cylindrical, as show-n in Figs. l

and 5, and of reduced dimension at .the tivo ends, which are provided with .internal screw threads 18 as shown in Fig. 43. The

coupling may be conveniently formed from suitable .blanks or sections of metal pipe by ycoin-pression in dies which actto compress the metal bodily :inward and not only give it the proper shape .but render it more dense land tough. The cou-plingsrare preferably pressed into shape by means ot the machine .disclosed in my application S. N. 358449 ined February 1.3, 1926. The couplings are strengthened the ribs l- Which are pro- Ivided by the surplus material-Which results when the ends ot the-blank are contracted in the dies. 'Theelevations l-l .also strengthen the internally-threaded end portions of the couplings these elevations Iare -rformed l s ie the surplus material which is prov-iced when the ends Joi the blank rare contracted in the dies. By referring to Figs. U1 and in connection with Fig. which Acoupling in longitudinal section 'ged scale,` itivill be seen that the coupling includes .a Vcontinuously tubular member having a middle portion, the interior of which is cylindrical in shape, and the exterior of which is polygonal in shape, the sides or faces of the polygon being designated by the numeral 10. llhe coupling also includes contracted or reduced end portions having a cylindrical interior forni throughout and having the polygonal exterior surfaces l2 adjacent the middle portion which Warped into cylindrical 'forni at the outer end of `the coupling to constitute the elevations i6. rEhe polygonal surfaces l2 are separated from each other by the outwardly projecting longitudinal ribs ld Which :eierably begin flush with the corners of the polygonal middle portion and extend c the ends oi' the coupling. The ribs le and the elevations 16 thus serve a tivo-fold purpose in strengthening the finished coupling and in taking care of surplus material when the ends ot' the blank are contracted to form the reduced end portions. rllhe end portions are interiorly threaded in the customary manner. The elevations 16 on account of being located on the inclined sides 12, and further on account of being substantially parallel With the faces of the middle portion, merge into the sides l2 of the polygcnal-shaped ends. rlhe surfaces of the lOl) elevations however, instead of being flat `are curved in a circumferential direction, so that as shown in Fig. 2, the outer surface at each end of the coupling is acylindrical surface broken at intervals by the outwardly-extending ribs 14. ln practice it has been found that the making of the end portions of the coupling of hexagonal shape permits the retention of the inner lcylindrical surface when the end portions are reduced by radial inward pressure in'dies without any the full length of the coupling and separating the faces thereof. It is well-known that articles of polygonal shape which are turned by the application of a tool become rounded atthe edges lying between the faces, so that theV tooliis liable to slip onaccount of fail-V ure to obtain a good hold on the article. By providing longitudinal ribs or ridges between the faces of the polygon, so that the tool engages the ribs rather than the faces, liability of the tool slipping is avoided.

I claim:

l. A coupling comprising a hollow member having a middle portion, and contracted interiorly-threaded end portions, the expolygonal in shape and the faces on the exterior of said end portions converging as they extend from said middle portion, the outer ends of said faces being substantially parallel with the corresponding faces of said middle portion. V

2. A coupling comprising a hollow member having a middle portion, contracted interiorly-tlneaded end portions, the exterior surfaces of said end portions being depressed below the exterior surface of said middle portion and all of said exterior surfaces being polygonal in shapeV and longitudinal ribs separating the faces uponV the exterior of said end portions, said faces converging as they extend from said middle portion, theV outer ends of said faces being substantially parallel with the corresponding faces of said middle portion.

3.V A coupling comprising a continuously tubular member having a middle portion andlcontracted interiorly threaded endportions, the exterior surfaces of all of said portions being polygonal in shape, and all of the faces of said end portions being uniformly depressed below the faces of said middle portion, and outwardly projecting longitudinal ribs ,separating the exterior faces of said end portions the inner ends'of said ribs being flush with the exterior surface of said middle portieri. Y Y

In testimony whereof l `hereunto ax my signature. Y

EDWARD E. JOHNSON. 

